实现法

package com.atguigu.java;
import static java.lang.Thread.sleep;
/**
 *使用同步方法解决实现Runnable接口的线程安全问题
 *
 * @author Dxkstart
 * @create 2021-05-07 18:02
 */
public class WindowTest4 {
    public static void main(String[] args) {
        //3.创建实现类的对象
        Window4 w1 = new Window4();
        //4.将此对象作为参数传递到Thread类的构造器中，创建Thread类的对象
        Thread t1 = new Thread(w1);
        Thread t2 = new Thread(w1);
        Thread t3 = new Thread(w1);
        //5.通过Thread类的对象调用start()
        t1.setName("窗口一:");
        t2.setName("窗口二:");
        t3.setName("窗口三:");
        t1.start();
        t2.start();
        t3.start();
    }
}
// 1.创建一个实现Runnable接口的类
class Window4 implements Runnable {
    private int ticket = 100;
    //2.实现类去实现Runnable中的抽象方法：run()
    @Override
    public void run() {
        while (true) {
            show();
        }
    }
    public synchronized void show(){//同步监视器：this
        if (ticket > 0) {
            try {
                sleep(50);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println(Thread.currentThread().getName() +
                    "卖票，票号为：" + ticket);
            ticket--;
        }
    }
}